Cathode-ray tube manufacturing apparatus



CATHODE-RAY TUBE mumcwuamc APPARATUS Filed July so; 1956 July 29, 1958 J. J. O'CALLAGHAN 6 Sheets-Sheet 1 fiE 630 0:592:

J. J. O'CALLAGHAN 2,845,043

CATHODE-RAY TUBE MANUFACTURING APPARATUS 6 Sheets-Sheet 2 July 29, 1958 Filed July 30, 1956 Hydraulic Fbwer Puck IN VEN TOR.

HIS ATTORNEY.

JEROME J. O'CALLAGHAN- July 29, 1958 J. J. O'CALLAGHAN CATHODE- RAY TUBE MANUFACTURING AP PARATUS Fild July 30,- 1956 6 Sheets-Sheet 3 JEROME J. O'CALLAGHAN IN V EN TOR.

HIS ATTORNEY.

July 29, 1958 CATHODE-RAY TUBE MANUFACTURING APPARATUS Filed July so, 1956 J. J. O'CALLAGHAN 6 Sheets-Sheet 4 FIG. 3A

FIG. 3

JEROME J. O'CALLAGHAN INVENTOR. v

HIS ATTORNEY.

July 29, 1958 J. J. OCALLAGHAN 2,345,043

CATHODE-RAY TUBE. MANUFACTURING APPARATUS Filed July so, 1956 a Sheets-Sheet 5 100 19s 19s I 222 A 225 i 7 223 V I 226 "Q;

HIS ATTORNEY.

CALLAGHAN 2,845,043

CATHODE-RAY TUBE MANUFACTURING APPARATUS Filed July so, 1956 July 29, 1958 6 Sheets-Sheet 6 JE ROME J. OCALLAGHAN INVENTOR.

HIS ATTORNEY.

United States Patent CATHODEFRAY. TUBE MANUFACTURING APPARATUS Jerome-J; OCall'aghau, Sliokie,=lll.,assignor to The Rimlaml Gorporafimnna corporation of Illinois Application July 30, 1956, Serial No. 600,851

23 Claims. (Cl. 118-408) This invention relates to cathoderay tube manuface turing; apparatus; more particularly, it has todo with a conveyor. apparatus. on. which a. series of cathode-ray tube. bulbs are successively screened and. filmed: automatically.

Numerous. attempts to mechanize the manufacture. of. cathode-ray picture tubes have been. carried. out. with. varied degrees of success. The conventional. methods of applying luminescent screens onto. the faceplates of the cathode-ray tube bulbs have undergone considerable change since the advent of. widespread commercial television; the continual striving for more economical tube production has resulted in the expenditure of large. sums of money and man-power. to the end. of providing. a machine which will. carry out the process of. applying a luminescent screen in a. completely automatic manner. and" which. will accomplish this result efiiciently and. dependably.

With the advent of aluminizedv television screens, it became desirable to apply a film. of organic material over the back surfaceof the luminescent screen; it likewise is highly desirable that the. film applying process be completely mechanized. It has. been appreciated. that this filming, process could best be carried out on the. same apparatus that is. utilized to apply the luminescent screens, since more eflicient and economical operation would result from the attendant reduction. of. bulb. handling.

7 Various approaches at mechanization have been tried, usually'involvi'ng, the use of. a continuously moving. conveyor ontowhich the bulbs are loaded. at. one end, are carried slowly along beneath. associated screening and filming, apparatus, and finally are carried around and under the other end of the conveyor to decant. excess settling. solution out .of the screen. and filmed bulb. However, it has been found that the shrinkage rates tend to run excessively high; a. shrinkagev rate is; a measure of the percentage of unsatisfactory tubes. produced by the screening andfilming apparatus. Rejection of the bulbs may be the result of anyof various. reasons, including uneven distribution of. settled phosphors or of the film, lackof proper adherence of either the phosphor or the film, the application of. either too heavy or too light a layer of the phosphor or the film, or breakage of the glass portions of the bulbs during their conveyance on.the apparatus.

It is, therefore, a general object of the present invention to provide a new and improved cathode-ray tube screening, apparatus.

It is also an object of the present invention to provide an improved cathode-ray tube screening apparatus which is capable of applying luminescent screens of good quality, which is automatic in its operation, and which is efiicient' and economical to operate by reason of its capability' of producing screened and filmed cathode-ray tube bulbs'at lower shrinkage rates than heretofore possible.

It is a corollary object to provide animproved cathoderay 'tubescree'ning and filming apparatus which is capable 2' of producing a large output of screen. and filmed bulbs, in which the screening, and filming operations are combined into one continuous operation with resultant savings in space and". equipment, and which yet is simple to maintain. and dependable in operation.

It. is another object offthe present invention to provide an improved apparatus. ofthe above character in which breakage of the cathode-ray. tube bulbs isefiectively prevented.

lt-.is.a-.more detailed object to provide improved means for guidingconduits, coupled to associated screening and filming equipment, into. and out of the bulbs.

It is a further object of the present invention to prw vide a novel system for moving, the associated screening and". filming, equipment precisely in synchronism with movement of the bulbs on the conveyor.

Another object of the present invention is to provide an improved siphon system for removing settling solution from the cathode-ray tube bulbs and which is capable of continuous operation" without corrosion or cloggingof the parts'of'the system.

It is another object. ofthe present invention to provideanimproved dispenser for applying precise quantiti'es. of film solution evenly, and smoothly onto the surface. of'the. settling solution and which is capable of applying a uniform quantity of film solution over a long period of operation.

A still further object of the present invention is to. provide apparatus for correlating. the operation of the siphon and the film dispenser. so that the latter is capable of always dispensing film solution with a minimum of disturbance to the settling solution.

In accordance with one aspect of the present invention, in which a carriage is utilized to carry the associated screening or filming equipment and is disposed adjacent the conveyor upon whichthe cathode-ray tube bulbs are moved atapredetermined speed, a system for moving the carriage in synchronism with the conveyor comprises a hydraulic actuator for moving the carriage, a valve. coupled to the actuator, an operating member for the valve, and means cooperating with the operating member for effecting an increase in carriage speed when the latter lags behind the conveyor and for efiecting a decrease in carriage speed when the latter leads the conveyor, so that the. carriage is moved at. the same speed as that of the conveyor.

Cooperating with the system whereby the associated screening and filming equipment, or parts thereof; are moved in synchronism with the cathode-ray tube bulbs, is an apparatus for accurately guiding conduits from the screening'and filming equipment into the cathode-ray tube bulbs. This apparatus comprises. an actuator coupled through a. flexible linkage to the upper end ofthe conduit' for vertically moving the same between an upper position above the bulb and a lower'position at which the lower end of the conduit is below the neck portion of the bulb.. Means adapted to telescope over the conduit is provided for guiding the lower end thereof-into the neck, and the apparatus further comprises means in? eluding a lost motion connection between the guiding means and the conduit, for raising the former as the lower end of the latter is moved upwardly and, as. the conduit is lowered, for limiting, downward movement of the guiding means to a position about the neck while permitting continued downward movement of the conduit on into. the bulb.

Another'portion of the continuously operating screen ing and. filming apparatus is a dispenser for applying film solution onto the surface of settling solution contaihed within the bulb. The dispenser comprises means for storing film solution under a substantially constant head of pressure, means for projecting and withdrawing a 3 conduit coupled to the storing means into and out of the bulb, and a valve disposed in the conduit for slicing laterally through film solution flowing therethrough in order to terminate the flow of the film solution without imparting increased velocity thereto.

The invention also contemplates a syphon system for removing settling solution from the cathode-ray tube bulb. The siphon system comprises fluid operated suction means in combination with a conduit adapted for movement to immerse one end of the same into the settling solution and coupled at its other end to the suction means. A reservoir, containing used settling solution, is coupled to the suction means to deliver solution thereto and to receive solution therefrom. Means is provided for driving the solution from the reservoir through the suction means to operate the same so that the same solution is utilized as a driving fluid in the suction means as is being drawn thereby from the bulb. Finally, the siphon system comprises means for removing excess solution from the reservoir.

In the siphoning of settling solution from the cathoderay tube bulb, the invention contemplates drawing off the settling solution down to a very accurately determined level. This is accomplished by means comprising a conduit adapted to be vertically moved into and out of the bulb, together with means for producing suction at the conduit lower end. Means is provided for limiting downward movement of the conduit to a position at which the lower end thereof is at a predetermined level so that the solution is drawn out of the bulb only to the predetermined level. In order to prevent the flow of solution back out of the siphon conduit when the solution level drops below that of the conduit lower end, the apparatus further includes means for preventing such reverse flow of the siphoned solution in the conduit.

It is also contemplated to correlate the level of settling solution as accurately determined by the siphoning system with means for limiting downward movement of a conduit from the film dispenser so that the latter, in dispensing film solution onto the surface of the settling solution, has its lower end disposed only slightly above the settling solution surface, whereby the film solution flows evenly over the settling solution surface.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The organization and manner of operation of the invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:

Figure 1 is a side elevation, partially broken away and partially in schematic form, of an embodiment ofthe screening and filming apparatus of the present invention;

Figure 2 is a detailed fragmentary view; partially in cross-section, of the principal components of the synchronizing system embodied in the apparatus of Figure 1;

Figure 2A is similar to Figure 2 but with some of the parts in different positions;

Figure 3 is a fragmentary cross-sectional view of a portion of the siphoning system of the apparatus of Figure 1 and illustrates means for guiding a conduit accurately through the neck of the cathode-ray tube bulb;

Figure 3A is similar to Figure 3 but with the parts in different positions;

Figure 3B is a detailed cross-sectional view taken along the line 3B3B of Figure 3A;

Figure 4 is a schematic view of the overall siphoning system of the apparatus of Figure 1 arranged to illustrate one aspect of the invention;

Figure 4A is a fragmentary cross-sectional view of a Venturi-tube utilized in the siphoning system of Fig- V ure 4;

4 of a film dispenser constructed in accordance with the present invention and including a modified form of the guiding means shown in Figures 3 and 3A; and

Figure 5A is a detailed cross-sectional view taken along the line 5A-5A of Figure 5.

In the overall view of the embodiment shown in Figure 1 for purposes of illustration, a series of cathode-ray tube bulbs 20, supported with their neck portions 20a uppermost and their faceplates 20b horizontal, are carried horizontally from left to right by a conveyor 21 moved at a uniform speed by means of a drive motor 22 coupled to conveyor 21 through a gear-unit23 and a sprocket 24. Sprocket 24, at the right end of the apparatus, and a similar sprocket 25, at the other end of the apparatus, are journaled in bearings 26 mounted upon a stationary horizontal beam 27. Suitable conventional mechanism may be employed to maintain a constant tension in conveyor 21. Bulbs 20 are secured to conveyor 21 by means of hinged clamps 29.

Carried above conveyor 21 on a stationary track-way 30 supported by uprights 28 is a screening carriage 31 movably supported on track-Way 30 by rollers 32; trackway 30 is supported separately from conveyor 21 to minimize the transfer of vibration from one carriage to the conveyor. A piston cylinder 33 is mounted on carriage 31 and encloses a piston having a piston rod 34 atfixed at its outer end to a block 35 secured to trackway 30, extension of piston rod 34 being effective to move carriage 31 in the direction of movement of conveyor 21.

Carriage 31 includes equipment for first dispensing a measured quantity of a settling solution into one of the bulbs 20 and then for dispensing a measured quantity of a slurry including a luminescent phosphor into the previously injected settling solution. For injecting the settling solution, a conduit 38 is supported for vertical movement by a flexible linkage 39 guided over an idler gear 40 and aflixed to the piston rod 41 of a hydraulic actuator 42. Hydraulic actuator 42 is operated only in response to engagement of a conventional cam follower 43, moving from left to right, with a cam 44 supported by track-way 30. On the upper end of conduit 38 is a conventional dispenser 46 for delivering a measured quantity of settling solution from a reservoir indicated at 47 and operated in response to suitable micro-switches (not shown) during the time that conduit 38 is lowered to a preset position within one of bulbs 20. Mounted to telescope over conduit 38 is a neck-finder and guiding means 50 for accurately directing conduit 38 through neck portions 20a upon the down-stroke of conduit 38; a more detailed description of guiding means 50 is given below in connection with other figures.

For dispensing the slurry of luminescent powder into the settling solution previously dispensed through conduit 38, there is a conduit suspended from a flexible linkage 56 for vertical movement by means of a hydraulic actuator 57 keyed to operate by action of a cam follower 58 engageable with cams 44- in the same manner as actuator 42. A guiding means 59 is mounted on conduit 55 and is identical with guiding means 50. .At the upper end of conduit 55 is a mixing hopper 60 into which a measured quantity of powder is injected from a dispenser 61 together with solution from a reservoir indicated at 62, the solution and powder being thoroughly stirred by a mixer 63 and then, upon operation of a magnetic valve 64 keyed by suitable micro-switches to open when conduit 55 is projected within a bulb 20, the mixture or slurry is allowed toflow downwardly through conduit 55 into the body of settling solution 65 previously dispensed into bulbs 20.

A second carriage is carried on track-way 30 by means of wheels 71 and supports siphoning and film dispensing equipment. Carriage 70 is similarly driven by means of a hydraulic actuator including a piston cylinder 72 enclosing a piston from which a piston rod 73 extends; piston rod 73 is aflixed at its outer end toa block 74 supported by track-way 30.. Carriages 31 and 70 are controlled in their movement along track-way 30 by means of a synchronizing system which includes a valve 76 (shown only in connection with. carriage 70 for sake of clarity of the drawings, identical valves being employed for controlling the operation of actuators 33 and 72) having an operating member 77 engageable with one of a series of cams 7'8 aflixed on conveyor 21, one cam 78 being provided for each of the bulbs a detailed description of this synchronizing system is included below in connection with Figures 2 and 2A. Also cooperating with the synchronizing system is a stationary cam 79 carried on a frame-member 79a and which, as is described in more detail below, cooperates with valve 76 to limit movement of carriage 70 and cause reversal in its movement after a complete cycle of operation, as also described in more detail below. A similar cam (not shown) is provided in connection with carriage 31.

In the instant embodiment, carriage 70 supports equipment utilized in the filming portion of the overall process; included on carriage 70 are rough and fine siphon systems for removing a portion of settling solution 65 from bulbs 20, the rough siphon being capable of removing the settling solution at a high-volume flow rate and being operated to lower the solution level only approximately to a particular level desired in connection with the belowdescribed operation of the film dispensing equipment. This rough siphon system comprises a conduit 80 supported from a flexible linkage 81 afiixed to a hydraulic actuator 82 and controlled to effect: reciprocation of conduit 80, in the same manner asfor actuators 42 and 57, by means of a cam follower 83 engageable with cams 44. A guiding means 85 telescopes over conduit 80 in amanner identical with that of guiding means 50 and 59. Conduit 80 is coupled by a flexible hose 86 to a suction system indicated at 87 and describedin more detail in connection with Figure 4. Spaced in the direction of conveyor movement beyond conduit 80 is a fine siphon conduit 88 provided with a guiding means 89 and suspended by a flexible element 90- from a hydraulic actuator 91 responsive to a cam follower 92-, reciprocation of conduit 88 being: initiated in the same manner as that above described with respect toconduit 38. If desired, reciprocation. of both conduits 80- and 88 may be controlled by a single common actuator. Conduit 88 is coupled to suction system 87 by a hose 93 and is utilized for drawing off settling solution 65 down to a very accuratelypreselected level, about which more will be said in connection with Figure 3B.

Carriage 70 also supports a film dispenser for applying precisely measured amounts of. film solution onto the surface of the settling solution remaining in the bulbs 20 after the siphoning steps and arranged to insure the formation of an even film over the settling solution surface. The illustrated embodiment of the film dispenser includes a conduit 100 depending downwardly from a reservoir 101 supported by a flexible element 102 attached to a hydraulic actuator 103 controlled by a cam follower 104 to operate in the same manner as that above described with respect to conduit 38,. so as to lower conduit 100 successively into each of bulbs. 20 during their movement by conveyor 21. Conduit 100 also includes a guiding means 106 which. operates in a manner similarto that of guiding means 50 and. the others but which includes a modified construction as is indicated below in connection with Figure 5. The film dispenser includes a valve of special constructionv for controlling the flow of film solution intovbulbs 20, which valve is operated by an air cylinder 107 powered by an air source indicated at 108 upon the actuation of suitable microswitches which function in response to the lowering of conduit 100 to project its lower end into one of the bulbs 20. p

.. Power of all of. the hydraulic actuating devices is provided by a single hydraulic power pack indicated at 110, which may be of conventional construction including a reservoir of hydraulic fluid and a pump for maintaining hydraulic pressure in the system. Hydraulic power pack 110 is coupled to each of hydraulicactuators 42, 57, 82, 91 and 102; in addition, hydraulic power pack 1 10 is utilized together with valve 76 and the corresponding valve associated with carriage 31 to control the extension of piston rods. 73 and 34 for moving carriages 70 and 31, respectively.

Portions of the above described apparatus are entirely conventional, and the general overall scheme of screening has heretofore been suggested. However, certain portions of the above described apparatus involve new and distinct departures from and improvements upon prior art apparatus of this type and, therefore, will be treated in. substantially more detail below. Before proceeding further, it is desirable to understand the general operation of the. apparatus shown in Figure 1. In operation, bulbs 20 are secured by clamps 29 onto conveyor 21 at the lefthand end of the apparatus. The bulbs are then carried smoothly and evenly from left to right while" they undergo the several above mentioned operations. Initially, a measured amount of settling solution 65 is introduced. into each of the bulbs 20' through conduit 38. During the initial filling period, conduit 38 is lowered to project its lower end within the bulb while the bulb continues its uniform movement, the synchronizing system being effective to move conduit 38 from left to right in precise step with the bulb movement. Subsequently, after conduit- 38 has been withdrawn, carriage 31 is moved to the left to bring conduit 55 into a position where it is lowered into the bulb 20 previously filled with settling solution 65. Again, carriage 31, and hence a conduit 55 is moved along precisely in step with the bulb movement during a period of time when the powder slurry from hopper 60 is flowing through conduit 55 into settling solution 65.

After the powder slurry has been introduced into the bulbs 20, the powder settles through settling solution 65 during the time interval elapsing as conveyor 21 moves the bulbs progressively along toward a position beneath conduit of the rough siphon. Byv the time conduit 80 is lowered to immerse its lower end into solution 65, a desired amount of phosphor has settled into adhering relation with faceplate 20b. After the rough and fine siphoning steps, respectively by means of conduits 80 and 88, film dispenser conduit is lowered to a position at which its lower end is slightly above the surface of the remaining amount of solution 65, and film solution from reservoir 101 is floated over the settling solution surface. After withdrawal of conduit 1 00, the remaining settling solution is decanted from bulbs 20 out from under the solidified or partially solidified filmlayer during travel of the bulb around sprocket 24 at the righthand end of Figure 1. During the decanting, the film layer first affixes itself to the upper inside portions of the bulb near faceplate 20b and then, as the bulb is tipped outwardly, the film layer falls smoothly over the faceplate as the water is poured off out from under the film layer. After decanting of the excess solution, the bulbs are returned.

along the underside of the conveyor to the loading station, at the left end of Figure 1, from where they are removed:

.The general advantages resulting from the moving of the bulbs 20 slowly and evenly along their path of travel are old and well known in the art; more accurate and even settling of the luminescent powder is obtained by preventing agitation or sloshing of solution 65. Hence,

frame 28 is of rugged construction and the entire assemblage is constructed of heavy, strong materials and preferably is firmly secured to a suitable foundation. The settling solution and powder dispensers may be of previously known design and may be in any suitable form; however, the guiding means 50 and 59 cooperating therewith 'atford decidedly improved operation over that" of '7 prior apparatus of this type by insuring that the conduit is projected within the bulb. In addition, it is desired to employ suitable conventional apparatus to prevent operation of the raising and lowering mechanisms in the absence of a bulb in a particular set of the clamps 29.

Figures 2 and 2A taken in combination with Figure 1 illustrate the carriage synchronizing system of the present embodiment of the invention; for clarity, the size of valve 76 is greatly exaggerated with respect to the length of piston cylinder 72. Valve 76 includes a valve body 112 enclosing a valve stem 113 biased by a compression spring 114 in a direction outwardly of the lower end of the valve. From left to right in Figure 2, valve stem 113 comprises a shank portion 115 bent upwardly at its outer end 116 and encircled by a collar 117, a first enlarged portion 118 slidable snugly within the bore 119 of the valve body, a necked-down portion 120, a second enlarged portion 121, a throttling portion 122 of tapering diameter, and a final enlarged portion 123 terminating in a collar 124 limiting downward movement of valve stem 113 by abutment with a surface 125 on the internal portion of the valve. An L-shaped operating member 130 is pivotally mounted on a pin 131 through one leg of the L and outer shank end 116 of valve stem 113. At the end of the other L leg is a cam-follower roller 132 secured thereto by a pin 133. Normally, the base edge 134 of member 130 abuts against collar 117 so that pressure on the extreme outer end of operating member 130 tends to move valve stem 113 into the valve, compressing spring 114.

Valve body 112 is provided with five valve chambers 135, 136, 137, 138 and 139, respectively, from left to right in Figure 2. These chambers are formed by a respective succession of inwardly projecting annular lugs 140 having internal diameters that snugly receive the pertions 118, 121, and 123 of valve stem 113. Chambers 135 and 139 are internally connected by a duct 142 which communicates with the hydraulic fluid input from power pack 110. The middle chamber 137 is coupled to a fluid return line to power pack 110. Chamber 138 is coupled by a line 144 to the righthand space 145 of iston cylinder 72, while chamber 136 is coupled by a line 146 to the lefthand space 148 in cylinder 72.

Valve 76 is of conventional four-Way valve construction with one important exception: portion 122 is especially machined to provide a tapered throttling surface which cooperates with chambers 1'38 and 139; portion 122 tapers evenly from the diameter of adjacent portion 123 down to a diameter substantially smaller than the next succeeding portion 121. carriage 70 so as to be movable therewith and is disposed to position roller 132 in the path of cams or rollers '76 as they are moved along by conveyor 21. As shown, pin 133 lies below an imaginary line joining the center of cam-roller 78 and pivot pin 131 when roller 132 is engaged with the periphery of cam-roller 78. A second cam-follower 151) projects outwardly from operating member 130 (upwardly from the plane of the drawing) and is disposed to come into engagement with cam 79 (disposed upwardly of the plane of the drawing with respect to valve 76) whereupon the upwardly slanting cam surface 151 thereof deflects operating member 130 upwardly around pin 131. There is thus provided a toggle mechanism which is locked when cam 78 pushes on roller 132 but which unlocks permitting member 130 to fly upwardly upon engagement of cam surface 151 with camfollower 150, whereupon valve stem 113 moves outwardly by the urging of spring 114.

The positions of the parts in Figure 2 corresponds with that of Figure 1 wherein carriage 70 is just beginning its movement from left to right and shortly before actuators 82, 91, and 103 are operated to lower their respective conduits downwardly into the respective bulbs 20. In this position, a cam 78 has come into engagement with roller 132 to force valve stem 113 inwardly of valve body 112 whereupon a small opening exists between valve stem portion 122 and the adjacent lug 140 to provide communication between chambers 139 and 138. At the same time, free communication is provided between chambers 136 and 137 by virtue of the position of reduced stem portion which is spanning the lugs separating these two chambers. In this position, hydraulic fluid from power pack 110 flows through duct 142, chamber 139, chamber 138, line 144, and into piston space 145. Returning from the other piston space 148, a path is provided through line 146, chamber 136, and chamber 137 back to power pack 110. As fluid is thus caused to How into chamber 145, piston cylinder 72, and hence carriage 70, is urged to the right. Any tendency of carriage 70 to move at a faster speed than that of the conveyor, and thus to lead the latter, permits movement of valve stem 113 in a direction downwardly out of valve casing 112 because of the urging of spring 114. This outward movement of valve stem 113 moves its portion 122 slightly to the left further restricting the communication space between chambers 139 and 138 and thereby reducing the rate of fluid flow through those chambers to piston space 145; thus, when carriage 70 tends to lead conveyor 21, valve 76 instantly responds by reducing hydraulic fluid flow to reduce the carriage movement speed. On the other hand, if carriage 70 starts to lag behind conveyor 21, roller 132 rides on cam 78 and thereby forces valve stem 113 inwardly against the biasing force of spring 114 to cause an instantaneous opening of the communication between chambers 139 and 138 to etfect an increase in carriage movement speed. Therefore, it is seen that this system, which is very simple to construct and assemble, causes carriage 70 to move precisely in synchronism with conveyor 21 within the limits of piston travel.

After being synchronously moved along with conveyor 21 for a period of time suflicient to allow dispensing, siphoning, and retraction of the conduits, carriage 70 is caused to reverse its direction of movement and return to its initial starting position whereupon the cycle is repeated for the next succeeding bulb. This limiting of carriage movement occurs upon engagement of camfollower 150 with cam surface 151 on cam 79. The latter is positioned to deflect operating member upwardly about pin 131 whereupon cam follower 132 is swung clear of cam 78 to permit spring 114 to force valve stem 113 to its completely extended position shown in Figure 2A. Cam 79 retains operating member 130 in its upward position until cam 78 has been moved by conveyor 21 on past and beneath cam-follower 132, while at the same time carriage 70 has started its return movement so that, when cam-follower 150 is moved free of calm surface 151, operating member 130 is by its own weight brought back to its normal position with its base surface 134 abutting agaianst collar 117. In this position of operating member 130, cam-follower 132 is in a position to be engaged by the next succeeding cam 78 which cam then pushes valve stem 113 back within valve body 112 to again establish the synchronized tracking of carriage 70 with conveyor 21. The return stroke is caused upon extension of valve stem 113 by a different resulting combination of the valve chambers with the valve stem portions. In this instance, hydraulic fluid from power pack 110 is conducted through duct 142, chamber 135, chamber 136, and line 146 to space 148.

y This urges piston cylinder 172 to the left, the return fluid path being from space through line 144, chamber 138, and chamber 137 back to power pack 110.

Movement of carriage 31 is controlled by an identical valve and cam arrangement and therefore it is unnecessary to incorporate any detailed description of the synchronizing system for carriage 31.

From the above, it will be evident that for each successive cathode-ray tube bulb, carriages 31 and 70 come into synchronous movement with the bulbs during a time interval .in whichv various conduits are lowered, in respouse to engagement of'the different actuator cam-fol lowers with their: respective cams 44;- tot-vproje'c't the con duit lower ends through. neckportions 20w into the-bulbs; Although the synchronizing system moves carriages and 70 in precise synchroni'sm with conveyor 20, it is also necessary toinsure accurate-positioning ot the reciprocating. conduits with respect to the bulbs during projecting of the conduit lower ends into the bulbs. Such accurate positioning is accomplished in the: present invention by utilizing the guiding means for insuringtha't'j each of the conduit lower ends is directed" accurately within the necks 20:. Once a conduit hasbeen lowered within the bulb, the synchronizing system maintains the move ment of the conduit in step with bulb-movement.

Although such a guiding means has beenemployed on each of the difierent vertically reciprocating conduits of the present embodiment, it is only necessary to provide a detailed description of one of them; Figures 3- and 3% show a detailed view of guiding means 89 employed on the fine siphon conduit 88; guiding means 50, 59, and 85 may be of identical construction. At its upper end, where it is connected to hose 93, conduit 88' is secured to flexible chain 90- by a U-shaped strap 1 60- pivotally connected to chain 90 by apin 1 61 and secured' about a bushing 162 clamped onto the conduit. Slidable over conduit 88-, in telescoping relationth'erewith, is" a sleeve 164 aifixed at its lower end to an inverted funnel-shaped member 165. In Figure 3', the flared portion of member 165 is encased within a box 166 rnounted upon the floor 70a of carriage 70; a hole-1671s cutinto-the'top' portion 167a of box 166 through which the apparatus may be raised and lowered. The side portions of box 166 project downwardly toward bulbs 20, the box being open on its underside and the lower'edges of box 166' being spaced above neck portion 20w by'a distance sufficient to permit lateral movement of member 165when the latter is lowered to dispose the rim of its flared portion below box 166 (Figure 3A). Guiding" means 89 is carried on conduit. 88 by inwardly projecting lugs I68 rigid with sleeve 164 and, as shown in Figure 3, restingon the upper surface of a collar 169 aflixed on conduit 88; Downward movement of guiding means 89 is limited by engagement of a collar 170 rigid with sleeve 164' which, upon lowering of conduit 88, abuts against box surface 167:.

The operation of guiding. means 89" is best understood by a comparison of Figures 3 and 3A which show guiding means 89 in its raised and lowered positions, respectively. In Figure 3, chain 90 is pulled upwardly whereupon guiding means 89 is disposed in its upper position with its lugs 168 resting on collar 169. When chain 90 is extended downwardly (by operation of actuator 91 in Figure 1), guiding means 89 is carried downwardly by conduit 88 until collar 170 lands on box surface 167a; conduit 88 then continues its downward movement on into bulb 20. The flared portion of member 165' defines a downwardly and outwardly tapering cam surface which, as the entire assembly is lowered toward bulb 20, engages with the upper end of neck portion 20a and guides the entire assembly into a centered position over. bulb 20 so that, as conduit 88 continuesits downward movement on into the bulb, its lower end170a is. disposed. to enter neck portion 20a. If, upon; lowering. of guiding means 89 toward bulb 20, the latter is notcentered beneath conduit 88, guiding means 89 is free to move laterally in any direction as soon as; the outer rirm of the flared portion clears the lower edge or box. 16.6; thus, accurate centering and alignment. of conduit 88-with neck portion 20a. is insured.

In order to remove solution. 65: from; bulk 20' to" a precise level, it is first necessary to. accurately relate the lengths of the various components, and. the spacings thereof. This is accomplished in the presentiinstance: by accurately selecting the distance that: conduit 88 projects below: the free ends- 1872 of strap to: correspond with the precisely determined spacing of. top surface 167:: above conveyor 21,- against which faceplate 20b is disposed. As the entire assemblage is lowered, collar first lands on top surface 167a and then strap end surface 172- abuts against the upper'end of sleeve 164. This accordingly limits downward movement of lower end P700: toa precise distance above conveyor 21.

If a small diameter tube. is utilized for conduit 88, accurate" siphoning is readily obtained. However, for more rapidbperatio-n, it is desirable to use a fairly large diameter conduit 88, perhaps substantially larger than. inch in internal diameter. With a large diameter conduit, siphoning proceeds satisfactorily until the desired level is reached and air' is drawn up into the conduit along with the solution. It is acharacteristic of large diameter siphon conduits that when air is sucked up alongiwithliquid, the air tends to break up the solution column being. pulled upwardly and allows solution already drawn into? the conduit to run back out of it; thus, itis difiicult to obtain a precise siphon level a large diameter conduit. This problem is obviated. byproviding means for preventing the flow of siphoned. solution back. out of the siphon conduit whenthe settling: solution level drops below conduit lower end 170a. While a conventional check valve, a magnetic valve, and the like may be employed in accordance with the present invention, it is preferred to utilize a cup-shaped member 1 80-afiixe-d to conduit. lower end'170 asshownin Figure 3B. Member is disposed with its open end 181 uppermost and in covering relation toconduit lower end portion. 170a, the rim. 1:82 of member 180- being above the extreme lower end 188 of conduit 88'. The cup-shaped member is afiixed to conduit 88 by webs affixed to a collar 186 pressed onto lower end portion 170a. The undersurface of member 180. preferably is tapered comically to a point. to minimize drip ping of the solution from the undersurfa'ce as member 180 is pulled out of the bulb by causing solution on the undersurface to rapidly drip off the point immediately as member 180 leaves thesolution surface.

As solution 65 is drawn upwardly throughconduit 88, the level of the solution in the bulb drops until it is even with rim 182; thereupon the level of solution within member 180 is decreased by the continuing action of the siphon. However, as soon. as a small amount of air is drawn into the bot-tom end 1 83 of conduit 88, the solution begins to run backwardly out of the conduit and again. covers conduit end 183 whereupon an unbroken column of solution is reestablished within the conduit. In operation, after the level of solution 65 within bulb 20 is brought down even with the level of rim 182, the level of solution within member 180 continuously fluctuates just above and just below conduit end 183; the solution within the conduit thus is prevented from running back out'over rim'182. A listener can hear a slurping sound as the solution column within conduit 88 is alternately disrupted and again r-e-esta'bli'shed. It will be evident that the. combination of distancesselected as above described. for accurately positioning the bottom end of conduit 88' at a selected distance above conveyor 21 likewise. accurately positions the level of rim 1 82 above the conveyor. Therefore, the combination of cup-shaped member 180 with an exacting selection of dimensions renders the siphon capable ofdrawing oif' solution '65 down to a level spaced precisely above the conveyor.

While various types of suction pumps may be utilized in cooperation with conduits 80 and 88, consider-able difficulty has been encountered in maintaining operation of conventional siphoning systems because of the highly corrosive and precipitative elfectsof conventional settling solutions on the operating parts of the system. Figures 4 and 4A illustrate a. siphon system. which avoids. chemical reactions between settling solution 65 and the driving solution utilized in a suction producing means. The very simple and economical. arrangement shown in Figure 4 requires only a reservoir 190 containing used settling solution 65a and into which is immersed a pump 191 driven by a motor 192. Solution drawn out of reservoir 190 by pump 191 is driven by way of a line 193 through parallel connected Venturi-tubes 194 and 195. Each Venturi-tube has a drive inlet 196, a suction inlet 197 and an outlet 198. The suction inlet of Venturi-tube 194 is connected to hose 93, while the suction inlet of Venturi-tube 195 is connected to hose 86 (Figure l).

The operation of a Venturi-tube is well known; as shown in Figure 4A, the driving solution is forced through a restrictive nozzle 199 from which it emerges as a highvelocity stream which is directed through a converging chamber 200 toward outlet 198. The action of the Venturi-tube is to produce a suction in a duct 201 communieating with chamber 200 and which in turn produces a suction at inlet 197. Ordinarily, water from commercial mains is utilized to operate such a Venturi-tube siphon system; however, the settling solutions utilized in the screening steps chemically react with ordinary water to produce precipitants which quickly clog Venturi-tubes 194 and 195. The present system avoids such chemical reaction by the expedient of using the same solution drawn from bulbs 20 as a driving solution for the V-enturi-tubes. The driving solution is driven through Venturi-tubes 194 and 195 and is returned to the reservoir from outlets 198 through a duct 1980 along with the freshly siphoned solution drawn through hoses 86 and 93. Since the amount of solution in reservoir 190 is continually being increased, an overflow drain 202 is provided on the reservoir.

Figure 5 shows in detail the film dispenser mentioned above with respect to Figure l and comprising a conduit 100 suspended from a flexible linkage 102. Figure 5 also illustrates a guiding means 106 which is a modified form of guiding means 89 shown and described with respect to Figures 3 and 3A. In this instance, guiding means 106 utilizes an identical sleeve 164 secured to an inverted funnel-shaped member 165 slidable within a box 166 affixed to floor 70a and having a hole 167 in its top surface 16711. Also, sleeve 164 has the same collar 170 adapted to land on surface 167a and which, in cooperation with the upper end of sleeve 164 and the different vertical dimensions, limits downward movement of first the guiding means and then conduit 100 to predetermined positions. The difference between guiding means 106 and 89 resides in the type of lost-motion connection between guiding means 106 and conduit 100. In this instance, conduit 100 is carried at its upper end portion 210 by means including a housing 211 hooked onto flexible chain 102. The bottom surface 212 of housing 211 abuts against the upper end of sleeve 164 to limit downward movement of conduit 100 and thereby to determine the lowermost position of the conduit lower end 214. Flexible means such as chains 215 is connected between bottom surface 212 and collar 170; as shown in Figure 5 wherein conduit 100 is in its lower position, chain 215 is slack, the excess links piling on top of collar 170. However, as flexible linkage 102 pulls the conduit upward-1y, chain 215 becomes taut after conduit lower end 214 is raised to a position above neck 20a and, as conduit 100 continues to move upwardly, guiding means 106 also is raised free of neck portion 20a, so that, after the withdrawal of conduit 100, carriage 70 may be moved back to its initial position ready for the next cycle. For guiding conduit 100 within sleeve 164, a pair of bearings 217 and 218 are secured respectively within the upper and lower parts of sleeve 164.

More particularly with respect to the film dispenser itself, reservoir 1'01 is relatively wide as compared with its height, the upper end of conduit 100 being coupled into the bottom of reservoir 10.1 so that film solution 220 stored therein fiows downwardly from reservoir 101 through conduit 100. For controlling the flow of film solution 220 through conduit 100, a special valve is disposed in conduit lower end portion 214. As shown in detail in Figure 5A, this valve comprises a valve stem Cir 222 which is journaled in the bore of and cooperates with a hollow valve cylinder 223 pressed within lower conduit end 214. Valve stem 222 is an elongated rod extending through reservoir 101 and coupled at its top end by a lever 224 to air-cylinder 107 which, when actuated by compressed air from source 108, causes valve stem 222 to rotate. Near the lower end of valve stem 222 is a longitudinal groove 225. Another groove 226 is cut longitudinally partially along the bore of valve cylinder 223; groove 225 is positioned on valve stem 222 to span the remaining, ungrooved portion of valve cylinder 223 when valve stem 222 is turned to vertically align grooves 225 and 226. Valve stem 222 is of a diameter less than the internal diameter of conduit so as to provide a space 227 which is filled with solution from reservoir 101. With valve stem 222 turned as shown in Figure 5A, the flow of solution in conduit 100 is prevented; however, when valve stem 222 is turned to align grooves 225 and 226, solution flows from space 227 through grooves 225 and 226 from where it is conducted downwardly through a duct 228 running through a plug 229 pressed into conduit 100 below valve cylinder 223.

The above described film dispenser achieves success in its operation for several reasons. The problem is to very evenly and smoothly apply the film solution onto the surface of settling solution 65. First of all, solution 65 is accurately siphoned down to a precisely controlled level which is controlled through the cooperation of accurate vertical dimensioning of conduit 88 and guiding means 89 and the similar accurate positioning of film dispenser conduit 100 by accurately dimensioning the latter with respect to the vertical dimensioning of guiding means 106 together with correlating the levels of top surfaces 167a associated respectively with each of the guiding means 85, 89 and 106. As a result of this cooperation between the siphoning and the positioning of lower conduit end 214, the bottom end 230 of duct 228 is disposed only slightly above the surface of solution 65 so that film solution flows through duct 228 smoothly onto the settling solution and does not cause appreciable ripple on the latter. Another leading factor contributing to the success of the film dispenser is the valve comprising stem 222 and cylinder 223; as stern 222 is rotated to move grooves 225 and 226 out of alignment and thereby terminate film solution flow, the column of film solution is sliced laterally. The result of cleanly severing the column of film solution is to terminate its flow without imparting increased velocity to the film solution remaining just below the valve, which increased velocity, if permitted, tends to propel the last drop or two of film solution into the settling solution whereupon uneven distribution of the film solution occurs. Another important aspect of the above described film dispenser is the maintenance of a substantially constant head of pressure on film solution 220. In use, reservoir 101 is of a capacity to store solution for a long period of time, preferably for at least a regular work-shift of the attending personnel. The pool of film solution 220 contained in reservoir 101 is substantially greater in width than in height, while conduit 100 preferably is many times as long as the height of film solution in reservoir 101; the length of conduit 100 preferably is well over an order of magnitude greater than the height of stored solution. As a result, the variation in the height of the film solution stored in reservoir 101 is but a very small percentage of the total length of the film dispensing apparatus and, hence, the pressure imparting downward movement to the film solution remains substantially constant during long periods of operation. Therefore, by controlling the action of air-cylinder 107 to hold the film solution valve in its open position for a constant time interval, a very closely controlled amount of film solution is always dispensed onto the settling solution surface. The control of the air-cylinder may be accomplished by any of numerous well known timing devices which may be either electrically or mechanically operated.

In a, commercial embodiment of the invention which has been operated steadily for several months while producing' screened and filmed cathode-ray tubes at a; commercially profitable and competitive shrinkage rate, the following typical parameters are employed. Bulbs. 20 are spaced approximately 20: inches apart on conveyor. 21 which; is moving uniformly at a speed: of approximately. 1% feet per minute. In the first step of the process-, a conventional 21 inch cathode-ray't'ube bulbis filled with about 22.5 liters. of a deionized water-electrolyte settling solution dispensed through conduit 3.8. In the next step of'the process, the powder slurry dispensed through conduit 55 is av mixture of 73.7 grams. of commercial grade fluorescent powder and 215 milliliters of potassium silicate in 500:;milliliters of deionized water. Rough siphon conduit 80 is spaced from powder dispensing conduit 55 by a distance such that the powder is permitted to settle for approximately 144 minutes. The rough siphon then takes the settling solution. level: down to about 2% inches above conveyor 21 after which fine siphon conduit 88 removes the settling solution. d'own to a precise level above conveyor 21 whereupon the depth of the remaining solution is. about two inches. Film dispensing conduit 100 is subsequently lowered to dispose lower end 230 of duct 238 exactly A; inch above the settling solution surface whereupon a few small drops, representing a fraction of one milliliter, of nitrocellulose lacquer, the film solution, is applied onto: the settling solution surface. Reservoir 101 is approximately oneinch in height and six inches in diameter, while conduit 100 is approximately 50 inches long. It must be emphasized that close attention to de tail is required to produce satisfactory screening and filming.

Each: of the above described features of the present invention contributes significantly to the overall success of the apparatus and all cooperate in the achievement of this success. The guiding means 50,59, 85, 89 and 106 not only accurately guide the different conduits into bulbs 20 but they cooperate with the conduits, particularly conduits 88- andl100, to accurately control the spacing of conduit 100 above the level of settling solution 65 during the film dispensing step of the process. The synchronizing system enables each of the different conduits to be moved along uniformly with bulbs 20 during each of the different steps of the process. The recirculation suction system, wherein the solution used for driving the suction producing means is the same as that solution which is being drawn through the latter means, enables continuous operation of the suction system and hence of the. entire. apparatus since all parts thereof must be capable of sustained operation. It will thus be seen that therehas been disclosed a screening and filming apparatus which is capable of producing, cathoderay tubes continuously day after day with only a minimum of attention and which requires only routine-maintenance to moving parts. v

While a particular embodiment of the present invention hasjbeen shown and described, it will be obvious to those skilled in the art that changes and modifications may be-made without departing. from. the invention in its broader aspects- Accordingly, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit andscope of the invention.

Iclaim:

1.. In av machine wherein a movable carriage member supports apparatus utilized for applying luminescent screens toa cathode-ray tube bulb-carried on a conveyor member moving, at a.predetermined speed, a system for synchronizing movement of said carriage with that of said conveyor comprising: means including a hydraulic actuator for moving said carriage member; valve means coupled. to said actuator; an operating element, movable with one of: said" members, for said valve means; and means, including a cam-surface movable with the other T4 of said. and engageable. with said operating element, for actuating. saidvalve means to effect an increaseeinl carriage speed when said carriage lags behind saidtconveyor and to effect a decreasein carriage speed when: said carriage leads said conveyor.

In a machine. wherein a movable carriage member supports apparatus utilized for applying luminescent screens. to a. cathode-ray tube bulb carried on a conveyor member moving at a'. predetermined speed, a system for synchronizing movement. of said carriage with that of said conveyor comprising: means including a hydraulic actuator for moving said carriage; a valve operating element movable with-one of said members; means, including a valve coupled tosaid actuator, responsive to movement of saidqoperating element in a first direction for effecting an increase in the speed of movement of said carriage and responsive to. movement of said operating element in a second: direction for effecting a decrease in said carriage movement speed; and means defining a cam-surface, movable with the. other of said members and disposed to come into engagement with said operating element, for moving the latter in said first direction when said con.- veyor 'istmoving faster than said carriage and for moving said operatingelementin said second direction when said carriage is moving faster than said. conveyor.

3:. In a. machine wherein a movable carriage member support-s apparatus utilized for applying luminescent screensto aeathode-ray tube bulbv carried on a conveyor member moving at a predetermined speed, a system for synchronizing movement of said carriage with that of said conveyor comprising: means including a hydraulic actuator for moving said carriage; valve. means coupled to said actuator; an operating element, movable with one of said members, for said valve; means, including a camsurface movable with the. other of said members and engageable with. said operating element, for effecting an increase in, carriagespeed when said carriage lags behind said, conveyor and for effecting a decrease in carriage speedwhen said carriage leads said conveyor; and means, includingja stationary cam-surface engageable with said opera-ting element when said carriage reaches a limit positionwi'n' the travel thereof, for causing a reversal in carriagemovement direction.

4'. Inv aimachine wherein a movable carriage member supports apparatus utilized for applying luminescent screens toacathod'e-ray tube bulb carried on a conveyor member-moving at a predetermined speed, a system for synchronizing movement of said carriage with that of said: conveyor comprising: means including a hydraulic actuator 'formoving said carriage; a valve operating element movable with one of said members; means, including a valve coupled to said actuator, responsive to movement of said operating element less than a predetermined amount in a first direction. for effecting an increase in the. speed of movement of said carriage, responsive to movement of said operating element in a second direction for effecting'a decrease in said carriage movement speed, and responsive to movement of said operating element more than: said-predetermined amount in said first direction. for effecting a reversal in direction of movement of saidcarriage; means defining a first cam-surface, movable with: the other of said first members and disposed to engage said operating element, for moving the latter less than said. predetermined amount in said first direction whenv said conveyor is moving faster than said carriage and; for moving said operating element in said second direction when said: carriage is moving faster than said conveyor; and. stationary means defining a second camsurface disposed: to engage said operating element when sa1d carriage reachesa limit position in the travel thereof for moving said operating element more than said predetermined amount in. said first direction to cause a reversal in carriage movement direction.

5. In a machine wherein a movable carriage member supports apparatus utilized for applying luminescent screens to a cathode-ray tube bulb carried on a conveyor member moving at a predetermined speed, a system for synchronizing movement of said carriage with that of said conveyor comprising: means including a hydraulic actuator for moving said carriage; a valve operating element movable with one of said members; means, including a valve coupled to said actuator, responsive to movement of said operating element less than a predetermined amount in a first direction for effecting an increase in the speed of movement of said carriage, responsive to movement of said operating element less than a predetermined amount in a second direction for effecting a decrease in said carriage movement speed, and responsive to movement of said operating element more than said predetermined amount for eflecting a reversal in direction of movement of said carriage; means defining a first cam-surface, movable with the other of said members and disposed to come into engagement with said operating element, for moving the latter less than said predetermined amount in said first direction when said conveyor is moving faster than said carriage and for moving said operating element less than said predetermined amount in said second direction when said carriage is moving faster than said conveyor; and stationary means defining a second cam surface disposed to engage said operating element when said carriage reaches a limit position in the travel thereof for moving said operating element more than said predetermined amount to cause a reversal in carriage movement direction.

6. In an apparatus wherein a conduit carried on a movable carriage member is utilized to dispense a film solution onto a settling solution contained within a cathode-ray tube bulb carried with its neck portion uppermost on a conveyor member moving at a predetermined speed, a system for moving said conduit in synchronism with said bulb during dispensing of said film solution, said system comprising: means including a hydraulic actuator for moving said carriage; valve means coupled to said actuator; an operating element, movable with one of said members, for said valve; means, including a camsurface movable with the other of said members and engageable with said operating element, for effecting an increase in carriage speed when said carriage lags behind said conveyor and for eflecting a decrease in carriage speed when said carriage leads said conveyor, whereby said carriage is moved at said predetermined speed; means, including a conduit, for dispensing said film solution in substantially constant predetermined quantities; and means on said carriage for projecting and withdrawing the lower end of said conduit into and out of said bulb through said neck portion during movement of said carriage at said predetermined speed.

7. In an apparatus wherein a conduit carried on a movable carriage member is utilized to dispense a film solution onto a settling solution contained within a cathode-ray tube bulb carried with its neck portion uppermost on a conveyor member moving at a predetermined speed, a system for moving said conduit in synchronism with said bulb during dispensing of said film solution, said system comprising: means including a hydraulic actuator for moving said carriage; valve means coupled to said actuator; an operating element, movable with one of said members, for said valve; means, including a camsurface movable with the other of said members and engageable with said operating element, for effecting an increase in carriage speed when said carriage lags behind said conveyor and for effecting a'decrease in carriage speed when said carriage leads said conveyor, whereby said carriage is moved at said predetermined speed; means including a conduit for storing a body of said film solution under a substantially constant head of pressure; means on said carriage for projecting and withdrawing the lower end of said conduit into and out of said bulb through said neck portion during movement of said car- 16 riage at said predetermined speed; and valve means disposed in said conduit for slicing laterally through film solution flowing through said conduit to terminate the flow of said film solution without imparting increased velocity thereto.

8. An apparatus for dispensing a film solution onto the surface of a settling solution contained within a cathoderay tube bulb supported with its neck portion uppermost, said apparatus comprising: means, including a conduit, for dispensing said film solution in substantially constant predetermined quantities; an actuator coupled through a flexible linkage to the upper end of said conduit for effecting vertcal movement of the lower end of said conduit between an upper position above said neck portion and a lower position below said neck portion; means, including a downwardly and outwardly tapering cam surface engageable with said neck portion, adapted to telescope over said conduit for guiding said lower end into said neck portion; and means including a lost-motion connection coupling said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower end is moved from said upper position toward said lower position, for limiting downward movement of said guiding means to a predetermined position about said neck portion while permitting continued downward movement of said conduit to a position at which said lower end is a selected distance above said settling solution surface.

9. An apparatus for dispensing a film solution onto the surface of a settling solution contained within a cathode-ray tube bulb supported with its neck portion uppermost, said apparatus comprising: means including a conduit for storing a body of said film solution under a substantially constant head of pressure; an actuator coupled through a flexible linkage to the upper end of said conduit for effecting vertical movement of the lower end of said conduit between an upper position above said neck portion and a lower position below said neck portion; means, including a downwardly and outwardly tapering cam surface engageable with said neck portion, adapted to telescope over said conduit for guiding said lower end into said neck portion; means including a lost-motion connection coupling said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower end is moved from said upper position toward said lower position, for limiting downward movement of said guiding means to a predetermined position about said neck portion while permitting continued downward movement of said conduit to a position at which said lower end is a selected distance above said settling solution surface; and valve means disposed in said conduit for slicing laterally through film solution flowing through said conduit to terminate the flow of said film solution without imparting increased velocity thereto.

10. In an apparatus for applying a luminescent screen to a cathode-ray tube bulb supported with its neck portion uppermost, the combination comprising: a conduit adapted to convey materials utilized in applying said screen; an actuator coupled through a flexible linkage to the upper end of said conduit for elfecting vertical movement of the lower end of said conduit between an upper position above said neck portion and a lower position below said neck portion; means, including a downwardly and outwardly tapering cam surface engageable with said neck portion, adapted to telescope over said conduit for guiding said lower end into said neck portion; and means including a lost-motion connection coupling said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower end is moved from said upper position toward said lower position, for limiting downward movement of 17 said guiding means to a predetermined position about said neck portion while permitting continued downward movement of said conduit.

11. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost, a siphon system for removing settling solution from said bulb comprising: a conduit disposed above said cathode-ray tube bulb; means coupled to said conduit for producing suction at the lower end thereof; an actuator coupled through a flexible linkage to the upper end of said conduit for effecting vertical movement of the lowerend thereof between an upper position above saidneck portion and a lower position below said neck portion; means, including a downwardly and outwardly tapering cam surface engageable with said neck portion adapted to telescope over said conduit for guiding said lower end into said neck portion; and means including a lost-motion connection coupling said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower end is moved from said upper position toward said lower position, for limiting downward movement of said guiding means to a predetermined position about said neck portion while permitting continued downward movement of said conduit into said settling solution.

12. In an apparatus for applying luminescent screens to a cathode-ray tube bulbsupported with its neck por tion uppermost on a conveyor member disposed at a predetermined level, a siphon system for removing settling solution from said bulb comprisingz a conduit disposed above said cathode-ray tube bulb; means coupled -'to said conduit for producing suction at the lower end thereof; an actuator coupled through a flexible linkage to the upper end of said conduit for effecting vertical movement of said lower end thereof between an upper position above said neck portion and a lower position below said neck portion; means, including a downward and outwardly tapering cam surface engageable with said neck portion, adapted to telescope over said conduit for guiding said lower end into said neck portion; means including a lost-motion connection coupling said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower end is moved from said upper position'toward said lower position, for limiting downward movement of said guiding means to a predetermined position about said neck portion while permitting continued downward movement of said conduit into said settling solution to a position at which said lower end is a selected distance above said predetermined level; and means for preventing siphoned solution flow in a reverse direction back out of said conduit.

13. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost, a system for removing settling solution from said bulb comprising: fluid operated suction means having a suction-inlet, a drive-inlet, and an outlet; a conduit coupled to said suction inlet and having its lower end adapted to project through said neck into said bulb; an actuator coupled through a flexible linkage to the upper end of said conduit for effecting vertical movement of said lower end of said conduit between an upper position above said neck portion and a lower position below said neck portion; means, including a downwardly and outwardly tapering cam surface engageable with said neck portion, adapted to telescope over said conduit for guiding said lower end into said neck portion; means including a lost-motion connection coupling'said guiding means to said conduit for raising said guiding means as said conduit lower end is moved from said lower position to said upper position and, as said conduit lower'endis moved from said upper position toward said lower position, for limiting downward movement of said guiding means to a predetermined positionabout'said'neck portion while permitting continued downward movement of said conduit to immerse said lower end into said settling solution; a reservoir, containing used settling solution, coupled to said drive-inlet todeliver 'solutionthereto and coupled to said outlet to receive solution therefrom; means for driving used settling solution fromsa-id reservoir through said suction means to effect suction atsaid suction-inlet, whereby the same solution drawnfrom said bulb through said conduit is utilizedas a driving fluid in said suction means; and means for removing excess used settling solution fromsaid reservoir.

14-. In an apparatus wherein a conduit carried on a movable carriage member is utilized to remove'settling solution from a cathode-ray tube bulb carried with its neck portion uppermost on a-conveyor member moving at a predetermined speed, a system for movingsaid conduit in synchronism with said bulb during removal of said solution, said system comprisingumeans including-a hydraulic actuator for movingrsaid carriage; valvemeans coupled to said actuator; an operating element, movable with one of said members, for said valve; .means, including a cam-surface movablewiththe other of said members and engageable with said operating. element, for effecting an'increase in carriage speed when said carriage lags behind said conveyor and foreflecting a decrease in carriage speed-when said carriage leads said conveyor, whereby said carriage is moved at said predetermined speed; means on said carriage for projecting and withdrawing the lower end of said conduit into and out of said bulb through said neck portion-during movement of said carriage at said predetermined speed; means coupled to said conduit for producing suction at said lower end thereof; means for preventing siphoned solution flow in a reverse direction back out of said conduit; and means or limiting downward movement of said conduit to a position at which said lower end is a selected distance above said conveyor member, whereby, when said lower end is disposed at said position, solution within said bulb is drawn out only to the level of said-lower end. i

15. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost on a conveyor member disposed at a predetermined level, a siphon'system for removing settling solution from said bulb comprising: a conduit adapted for vertical movement to project and withdraw its lower end into and out of said bulb through said neck; means coupled to said conduit for producing suction at said lower end; means for preventing siphoned solution flow in a reverse direction-back out of said conduit; and means for limiting downward 'movem'ent'of said conduit to a position at which said lower end'is a selected distance above said predetermined level, whereby, when said lower end is disposed at said position,'solution within said bulb is drawn out only to the level'of said lower end.

16. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost on a conveyor member disposed'at a predetermined level, a siphon system for removing settling solution from said bulb comprising: fluid operated suction means having a suction-inlet, a drive-inlet, and an outlet; a conduit coupled to said suction-inlet and adapted for vertical movement to project its lower end through said neck portion into said settling solution; means for preventing siphoned solution flow in a reverse direction back out of said conduit; a reservoir, containing used soluuon, coupled to said drive-inlet to receive solution therefrom; means for driving used settling solution. from said reservoir through said suction Jmeans to effect su'ction at said suction-inlet, whereby the same solution drawn from said bulb through said conduit is utilized as a driving fluid in said suction means; means for removinggexcess used settling solution from said reservoir; and means for limiting downward movem'entof said conduit to a position at which said lower end is a selected distance above said predetermined level, whereby, when said lower end is disposed at said position, solution within said bulb is drawn out only to the level of said lower end.

17. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost, a system for removing settling solution from said bulb comprising: fluid operated suction means having a suction-inlet, a drive-inlet, and an outlet; a conduit with one end adapted for movement to project said one end through said neck into said bulb to immerse said one end into said settling solution and coupled at its other end to said suction-inlet; a reservoir, containing used settling solution, coupled to said drive-inlet to deliver solution thereto and coupled to said outlet to receive solution therefrom; means for driving used settling solution from said reservoir through said suction means to effect suction at said suction-inlet, whereby the same solution drawn from said bulb through said conduit is utilized as a driving fluid in said suction means; and means for removing excess used settling solution from said reservolr.

18. In an apparatus for applying luminescent screens to a cathode-ray tube bulb supported with its neck portion uppermost, a system for removing settling solution from said bulb comprising: a Venturi-tube having a suctioninlet, a drive-inlet, and an outlet; a conduit with one end adapted to project through said neck into said bulb and coupled at its other end to said suction-inlet; a reservoir, containing used settling solution, coupled to said driveinlet to deliver solution thereto and coupled to said outlet to receive solution therefrom; means for driving used settling solution from said reservoir through said Venturitube to create suction at said suction inlet, whereby the same solution drawn from the bulb through said conduit is utilized as a driving fluid in said Venturi-tube; and means for removing excess used settling solution from said reservoir.

19. In an apparatus for applying a film solution onto a settling solution contained within a cathode-ray tube bulb supported with its neck portion uppermost on a conveyor member disposed at a predetermined level, said apparatus comprising: a first conduit adapted for vertical movement to project and withdraw the lower end of said conduit into and out of said bulb through said neck; means coupled to said first conduit for producing suction at said lower end; means for preventing siphoned solution flow in a reverse direction back out of said conduit; means for limiting downward movement of said first conduit to a position at which said lower end thereof is a selected distance above said predetermined level, whereby, when said lower end is disposed at said position, settling solution within the bulb is drawn out only to the level of said lower end; means, including a second conduit, for dispensing said film solution in substantially constant predetermined quantities; means for projecting the lower end of said second conduit into said bulb after withdrawal of said first conduit therefrom; and means for limiting downward movement of said second conduit to a position at which said lower end thereof is spaced above said predetermined level by a distance slightly greater than said selected distance.

20. In an apparatus for applying a film solution onto a settling solution contained within a cathode-ray tube bulb supported with its neck portion uppermost on a conveyor member disposed at a predetermined level, said apparatus comprising: a first conduit adapted for vertical movement to project and withdraw the lower end of said conduit into and out of said bulb through said neck; means coupled to said first conduit for producing suction at said lower end; means for preventing siphoned solution flow in a reverse direction back out of said conduit; means for limiting downward movement of said first conduit to a position at which said lower end 20 Y thereof is a selected distance above said predetermined level, whereby, when said lower end is disposed at said position, solution within said bulb is drawn out only to the level of said lower end; means including a second conduit for storing a body of said film solution under a substantially constant head of pressure; means for projecting the lower end of said second conduit into said bulb after withdrawal of said first conduit therefrom; means for limiting downward movement of said second conduit to a position at which said lower end thereof is spaced above said predetermined level by a distance slightly greater than said selected distance; and valve means disposed in said second conduit for slicing laterally through film solution flowing therethrough to terminate the flow of said film solution without imparting increased velocity thereto.

21. An apparatus for dispensing a film solution onto a settling solution contained within a cathode-ray tube bulb supported with its neck portion uppermost, said apparatus comprising: means including a conduit for storing a body of said film solution under a substantially constant head of pressure; means for projecting and withdrawing one end of said conduit into and out of said bulb through said neck portion; and valve means disposed in said conduit for slicing laterally through film solution flowing through said conduit to terminate the flow of said film solution without imparting increased velocity thereto.

22. An apparatus for dispensing a film solution onto a settling solution contained within a cathode-ray tube bulb supported with its neck portion uppermost, said apparatus comprising: means including a reservoir for storing said film solution in a pool substantially greater in Width than in height; a conduit communicating with said reservoir and projecting downwardly therefrom, said conduit having a length at least an order of magnitude greater than the height of solution in said reservoir; means supporting said reservoir above said bulb and adapted to raise and lower the reservoir to project and withdraw the lower end of said conduit into and out of said bulb through said neck; and valve means disposed in said conduit for slicing laterally through film solution flowing downwardly therethrough to terminate the fiow of said film solution without imparting increased velocity thereto.

23. In an apparatus for applying luminescent screens to a cathode-ray bulb supported with its neck portion uppermost, a dispenser for applying a film solution onto a settling solution contained within said bulb and having a vertically disposed conduit adapted to project and withdraw its lower end into and out of said bulb through said neck, said dispenser comprising: a reservoir, coupled at its bottom to the upper end of said conduit and substantially greater in width than in height, for storing said film solution; a valve disposed within said conduit for controlling the flow of film solution therethrough and comprising a hollow cylinder seated within said conduit and having a longitudinal groove in the bore thereof extending from one end of the cylinder partially along the length thereof, and a rod joinnaled in said cylinder and having a longitudinal groove extending along the surface thereof and adapted to span the portion of said bore between the groove therein and the other end of said cylinder; and means for turning said rod relative to said cylinder, whereby, a column of film solution flowing through said grooves when the latter are positioned in vertical alignment is severed laterally upon relative movement of said rod and cylinder to move said grooves out of vertical alignment.

References Cited in the file of this patent UNITED STATES PATENTS 2,646,769 Lindsay July 28, 1953 

